Antirez is taking a considered approach to this and weighing the very real time and technical cost to making an api change to a project the scale of Redis.

He has stated that if he were to start today, he'd use different terms. It's important to remember that even 10 years ago, life hadn't become as politicized as it is today. Master/slave was and is a very common technical term that does accurately describe the relationship.

All that being said, attacking open source developers of popular projects with politically motivated requests seems like a horrible idea. This guy did a ton of great work that many people have benefited from (for free) and now he's being bullied for even questioning if whether changing the API for a non-functional reasons is worth it.

We should treat the people who created something and offered it to the world for free with a bit more respect.